1. Field of the Invention
The present invention is related to a data processing apparatus which is applicable to a personal computer, a small electric device or the like which has a function of displaying information in the form of a chart, etc., and processing information.
2. Description of Related Art
Some application software used in a personal computer and some small electric devices such as an electric scheduler include data processing apparatuses which display information in the form of a chart, etc., and process information. A data processing apparatus has a chart preparation function of storing and displaying character strings, for example, in the form of a chart and a chart calculation function of calculating the character strings which are stored in the chart.
A chart used in a data processing apparatus is formed by successively arranging plural regions which are rectangular regions, for instance, in the form of a matrix. In each region, information to be stored, such as character strings, is accordingly displayed. In such a chart, a group of plural regions which are arranged vertically is called "a column." Similarly, a group of plural regions which are arranged horizontally is called "a row."
In a data processing apparatus which is used in a small electric device or the like, a chart which is formed by plural regions each storing no information is set in advance in most cases. When this chart is visually displayed, the respective regions are partitioned by frames which are formed by ruling lines, for example. This makes it easy to visually recognize and judge the size of each region. A user of the data processing apparatus enters and displays information, such as figures, formulas and characters, within the respective regions. The data processing apparatus performs editing, such as deleting, copying and cutting/pasting, row by row and column by column, on the information which is displayed in the form of a chart.
The user can also create the regions of the chart each in an optional size. Japanese Patent Unscreened Application Gazette No. 6-75953 discloses a technique of making it easy for the user to create the frames which partition the regions.
In most cases, the sizes of the regions are set before information is entered in the regions. When character strings which express the entered information are displayed in a character size which is set during entering of the information, a display range which is needed to display the character strings may be equal to or larger than a predetermined size which is set for the regions. With the conventional technique described below, if a display range which is needed to display the entered character strings is larger than the predetermined region, the sizes of the regions and the characters can be automatically changed.
For example, Japanese Patent Unscreened Application Gazette No. 4-344562 discloses a technique of changing a character size of characters which constitute character strings so that a display range for displaying character strings does not exceed the predetermined region. On the other hand, Japanese Patent Unscreened Application Gazette No. 6-266743 discloses a technique of expanding the size of the predetermined region so that a display range for displaying entered character strings does not exceed the predetermined region.
The chart as described above is created regardless of the size of a display screen of a display apparatus of a small electric device or a personal computer which includes a data processing apparatus. Hence, in some cases, a display range which is needed to display the created chart becomes larger than the size of the display screen, whereby it is impossible to display the entire chart in the display screen at a time. In such a case, if one wants to visually recognize two separated regions within the chart which are far away from each other by a distance larger than the size of the display screen and to grasp information which is displayed in each region, that person needs to move, e.g., scroll an image of the chart which is displayed in the display screen so that each region to be observed is moved into the display screen at one time and the person can look at the regions in a time-shared manner.
In the conventional electric device, the image of a desired chart is divided into plural images which can be displayed within a display range that is smaller than the size of the display screen. The divided images are switched and each displayed within the display range, and a region to be observed is displayed.
As described above, when the display range which is needed to display the chart is larger than the display screen of the electric device, it is necessary to move the image of the displayed chart during switching of the region to be observed. To move the image of the chart in this manner, a complex operation such as scrolling or switching of the image is needed. A small electric device such as an electric scheduler, in particular, has a small display screen, so that it is necessary to divide the chart into a number of images. In such a case, it is necessary to frequently switch a displayed image.
A display method which displays information as a chart is advantageous in that it makes it easy to compare information by displaying a plurality of related pieces of information next to each other. As described above, if it is impossible to look at regions which display information to be compared at one time, it is difficult to compare the information. When the chart consists of a number of rows and columns, and the information to be compared is displayed on a region which exists within the chart, comparison of the information is even more difficult.
To display a plurality of related pieces of information next to each other and to temporarily conceal information which is displayed within the chart, the regions are deleted, row by row and column by column. A row or a column to be deleted is different depending on in which row or column the information to be compared belongs to, and therefore, a row or column to be deleted is changed every time information to be compared is changed. After a row or column is deleted and comparison of information is performed, if the information is to be compared with other information using the same chart, a deleted row or column in some cases must be restored to the original position of the row or column.
Only a user who deleted a row or column can remember the delete position at which the row or column was deleted. Hence, the user forgets the delete position a while after deleting and does not know where to restore the row or column any more. In addition, since only the user who deleted a row or column can remember the delete position, it is difficult for other user who uses the same device to restore the row or column at the delete position.